TITLES OF PAPERS 229 



PRESENTATION OF PAPERS 



The presentation of scientific papers was then taken up as follows, 

 according to the program : 



SOME PROBLEMS OF MINERAL GENESIS IN SOUTH AFRICA 1 

 PRESIDENTIAL ADDRESS BY CHARLES PALACHE 



A STUDY OF CRYSTAL SYMMETRY ± 



BY AUSTIN F. ROGERS 



LATENT MEROSYMMETRY 

 BY EDGAR T. WHERRY 



USE OF PLANS AND ELEVATIONS IN TEACHING GEOMETRICAL 



CRYSTALLOGRAPHY 



BY AUSTIN F. ROGERS 



PLEA FOR ECONOMIC MINERALOGY 

 BY OLIVER BOWLES 



JERULE 'OF 'IB RITE, A NEW MINERAL 

 BY EDWARD T. H OLDEN 



CROC1DOLITE FROM EASTERN PENNSYLVANIA 

 BY EDGAR T. WHERRY AND EARL V. SHANNON 



OCCURRENCE OF MONOSULPHIDE OF IRON 

 BY ARTHUR S. EAKLE 



CRYSTALLOGRAPHY OF THREE RHODE ISLAND MINERALS 

 BY A. C. HAWKINS 



MINERALOGY FOR STUDENTS OF DENTISTRY 

 BY E. H. KRAUS 



WHITE CHLORITE FROM EASTERN PENNSYLVANIA 

 BY EDGAR T. WHERRY AND EARL V. SHANNON 



JADES OF MIDDLE AMERICA 

 BY HENRY S. WASHINGTON 



1 Read by Edgar T. Wherry in the absence of President Palache. 



